Terpolymers of alkyl acrylates or methacrylates, an olefinically unsaturated homo or heterocyclic-nitrogen compound and an allyl acrylate or methacrylate

ABSTRACT

Terpolymers having enhanced pour point depressant properties are disclosed which comprise (1) an alkyl ester of unsaturated monocarboxylic acid, (2) an olefinically unsaturated homo or heterocyclic-nitrogen compound, and (3) an allyl acrylate or methacrylate or a perfluoroalkyl ethyl acrylate or methacrylate. A process for preparing the terpolymers is additionally disclosed.

This is a continuation, of application Ser. No. 07/408,862 filed Sept.18, 1989, now abandoned which is a divisional of Application Ser. No.07/265,602 filed Oct. 31, 1988 now U.S. Pat. No. 4,900,569.

BACKGROUND OF THE INVENTION

1. Field Of The Invention

This invention relates to new compounds comprising terpolymers of alkylacrylates or methacrylates, an olefinically unsaturated homo orheterocyclic-nitrogen compound and an allyl acrylate or methacrylate orperfluoroalkyl ethyl acrylates or methacrylates and to the preparationof such compositions. These terpolymers are suitable for use as pourpoint depressants for a wide variety of oil compositions. The copendingapplication of Hanh T. Le entitled "Oil Compositions ContainingTerpolymers of Alkyl Acrylates Or Methacrylates, An OlefinicallyUnsaturated Homo Or Heterocyclic-Nitrogen Compound And An Allyl AcrylateOr Methacrylate Or Perfluoroalkyl Ethyl Acrylates Or Methacrylates",Ser. No. 265,626, filed Oct. 31, 1988, now U.S. Pat. No. 4,886,520describes oil compositions suitable for use in combination with theterpolymers disclosed herein, the disclosure of which is incorporatedherein by reference.

2. Description Of The Prior Art

Processes and catalysts for the production of polymers of alkylacrylates and alkyl methacrylates and/or heterocyclic-nitrogen compoundsare known and are currently practiced commercially.

For example, U.S. Pat. No. 2,889,282, issued Jun. 2, 1959, relates tolubricating oil compositions containing an oil soluble copolymerconsisting of (1) a monovinyl-substituted pyridine, and (2) a mixture ofa C₁₆ to C₂₀ alkyl ester of an acrylic acid and a C₁₀ to C₁₄ alkyl esterof an acrylic acid. The polymers are described as possessingparticularly good pour point depressing properties.

U.S. Pat. No. 3,260,728, issued Jul. 12, 1966, discloses a process forpolymerizing ethylene with lauryl methacrylate and n-vinyl-2-pyrrolidoneat increased temperature and pressure, using benzene as a solvent anddi-t-butyl peroxide as a promoter. The polymers are described as oiladditives which impart improved flow of fuel at low temperatures andimproved pour point characteristics to middle distillates.

U.S. Pat. No. 3,868,231, issued Feb. 25, 1975, relates to residual fuelshaving improved low temperatures flow properties. The residual fuel flowproperty is enhanced by the addition thereto of a copolymer of a C₁₈ toC₂₈ alkyl ester of acrylic acid and 4-vinylpyridine.

U.S. Pat. No. 3,957,659, issued May 18, 1976, discloses a copolymerwhich imparts improved low-temperature flow properties to crude oilshaving a high wax content. The copolymers consist of a C₁₄ to C₃₀ alkylester of acrylic or methacrylic acid and 4-vinyl pyridine.

U.S. Pat. No. 4,161,392, issued Jul. 17, 1979, relates to nitrogencontaining copolymers which are suitable for use as carburetordetergents and corrosion inhibitors. The copolymers consist of theolefin polymerization product of (1) a C₁ to C₄ alkyl methacrylate oraromatic ester of an unsaturated aliphatic mono-, di- or polycarboxylicacid, (2) a C₈ to C₂₀ saturated or unsaturated, substituted orunsubstituted, aliphatic or aromatic ester of an unsaturated mono-, di-or polyaliphatic carboxylic acid having 1 to 6 carbon atoms, and (3) anethylenically unsaturated compound containing a nitrogen atom, e.g.,dimethyl amino ethyl methacrylate acid or 4-vinyl pyridine.

It must be noted, however, that the specific terpolymers comprising thealkyl esters of unsaturated monocarboxylic acid, olefinicallyunsaturated homo or heterocyclic-nitrogen compounds, and allyl acrylateor methacrylate or perfluoroalkyl ethyl acrylates or methacrylatesclaimed herein are new.

SUMMARY OF THE INVENTION

This invention encompasses new compositions that are particularlysuitable for use as pour point depressants for oil compositions. Inparticular, the compositions comprise an alkyl ester of unsaturatedmonocarboxylic acid, an olefinically unsaturated homo orheterocylic-nitrogen compound and allyl acrylate or methacrylate or aperfluoroalkyl ethyl acrylate or methacrylate terpolymer having pourpoint depressant properties, said terpolymer comprising the reactionproduct of (a) a monomeric alkyl ester of carboxylic acid or a mixtureof alkyl esters of carboxylic acid having the formula: ##STR1## whereinR is H or CH₃ and R₁ is alkyl having from about 1 to about 30 carbonatoms; (b) vinyl pyridine; and (c) allyl acrylate or methacrylate or aperfluoroalkyl ethyl acrylate or methacrylate or a mixture ofperfluoroalkyl ethyl acrylates or methacrylates, said perfluoroalkylethyl acrylates or methacrylates having the formula: ##STR2## wherein R₂is H or CH₃, and K is an integer of from about 1 to about 20.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to terpolymers of alkyl acrylates ormethacrylates, an olefinically unsaturated homo or heterocyclic-nitrogencompound and an allyl acrylate or methacrylate or perfluoroalkyl ethylacrylates or methacrylates which are particularly suitable for use inoil compositions as pour point additives.

The alkyl acrylate or methacrylate monomers of the present invention areconveniently prepared by reacting the desired primary alcohol withacrylic acid or methacrylic acid in a conventional esterificationreaction. Direct esterification of acrylic acid or methacrylic acid withalcohols readily takes place in the presence of a strong acid catalystsuch as sulfuric acid, a soluble sulfonic acid or sulfonic acid resins.Another method of producing alkyl acrylates or methacrylates involvescontacting acrylic acid or methacrylic acid with a suitable olefin inthe presence of a strong anhydrous acid catalyst.

Typical examples of starting alcohols suitable for use herein includethe C₁ to C₃₀ primary alcohols. It should be noted that all of thestarting alcohols, e.g., the C₁ to C₃₀ alcohols, can be reacted withacrylic acid or methacrylic acid to form the desirable acrylates andmethacrylates.

Suitable alkyl acrylates or alkyl methacrylates contain from about 1 toabout 30 carbon atoms, especially from about 4 to about 28 carbon atoms,preferably from about 4 to about 24 carbon atoms in the alkyl chain.

Desirable alkyl acrylates are preferably selected from the groupconsisting of methyl acrylate, ethyl acrylate, propyl acrylate, butylacrylate, pentyl acrylate, hexyl acrylate, heptyl acrylate, octylacrylate, nonyl acrylate, decyl acrylate, undecyl acrylate, dodecylacrylate, tridecyl acrylate, tetradecyl acrylate, pentadecyl acrylate,hexadecyl acrylate, heptadecyl acrylate, octadecyl acrylate, nonadecylacrylate, eicosyl acrylate, heneicosyl acrylate, docosyl acrylate,tricosyl acrylate, tetracosyl acrylate, pentacosyl acrylate, hexacosylacrylate, heptacosyl acrylate, octacosyl acrylate, nonacosyl acrylate,and triacontyl acrylate and mixtures thereof.

Similarly, typical examples of the alkyl methacrylates include themethacrylates selected from the group consisting of methyl methacrylate,ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentylmethacrylate, hexyl methacrylate, heptyl methacrylate, octylmethacrylate, nonyl methacrylate, decyl methacrylate, undecylmethacrylate, dodecyl methacrylate, tridecyl methacrylate, tetradecylmethacrylate, pentadecyl methacrylate, hexadecyl methacrylate,heptadecyl methacrylate, octadecyl methacrylate, nonadecyl methacrylate,eicosyl methacrylate, heneicosyl methacrylate, docosyl methacrylate,tricosyl methacrylate, tetracosyl methacrylate, pentacosyl methacrylate,hexacosyl methacrylate, heptacosyl methacrylate, octacosyl methacrylate,nonacosyl methacrylate and triacontyl methacrylate and mixtures thereof.

It is to be noted that the individual alkyl acrylate or methacrylatemonomers can be incorporated into the terpolymers herein. However,mixtures of the alkyl acrylates or methacrylates are highly desirable inthe production of said terpolymers. Mixtures of alkyl acrylates ormethacrylates preferably contain 4 to 28 carbon atoms in the alkylmoiety.

The second monomer of the terpolymers herein comprises an olefinicallyunsaturated homo or heterocyclic-nitrogen compound which is commonlyreferred to as the vinyl pyridines. Originally vinyl pyridine, includingits homologs, which are selectively called pyridine bases, were isolatedfrom coal tar and coal gases, e.g., from the volatile by-products in thepyrolysis of coal. The noncondensable gas contains ammonia and most ofthe useable pyridine bases formed during coking.

More recently, vinyl pyridines have been prepared by the condensation of2- or 4- methylpyridine by heating in the presence of formaldehyde toyield the corresponding adol, e.g., 2-(2-hydroxyethyl) pyridine.Dehydration by treatment with base yields 2-or 4- vinyl pyridine or5-ethyl-2-vinylpyridine.

The preferred vinyl pyridine for use herein is 4-vinylpyridine, however,the 2-vinyl pyridine or 5-ethyl-2-vinylpyridine or mixtures of the abovecan be utilized to produce the desirable terpolymer.

The third monomer of the terpolymers herein is allyl acrylate ormethacrylate or a perfluoroalkyl ethyl acrylate or methacrylate or amixture of perfluoroalkyl ethyl acrylates or methacrylates, saidperfluoroalkyl ethyl acrylates or methacrylates having the formula:##STR3## wherein R₂ is H or CH₃, and K is an integer of from about 1 toabout 20.

The perfluoroalkyl ethyl acrylates or methacrylates herein canconveniently be prepared using conventional techniques and catalysts.For example, the starting compound perfluoroethylene is subjected to anoligomerization process to produce a perfluoroalkyl compound and theperfluoroalkyl compound is converted to perfluoroalkyl iodide. Next, theperfluoroalkyl iodide is reacted with ethylene or a similar compound toproduce perfluoroalkyl ethyl iodide and the iodide compound thusproduced is converted to an alcohol. Finally, the perfluoroalkyl ethylalcohol is reacted with either acrylic acid or methacrylic acid toproduce the perfluoroalkyl ethyl acrylate or methacrylate. It should benoted the chain length of the alkyl moiety of the compounds herein isdetermined by the number of perfluoroethylene groups added to the alkylmoiety during the oligomerization reaction.

The allyl acrylates or methacrylates herein are conveniently prepared bythe direct esterification of allyl alcohol with either acrylic acid ormethacrylic acid. The reaction is acid catalyzed, for example, bysulfuric acid or p-toluene sulfonic acid, and is driven forward by thecontinuous removal of water. One important method of removing water fromthe reaction medium includes the use of a ternary system or mixture. Tworepresentative ternary mixtures or systems include benzene-allylalcoholwater and diallyl ether-allyl alcohol-water. It should be notedthat the benzene and diallyl ether diluents lower the temperature in thereaction vessel; which in turn minimizes by-product formation,principally diallyl ether.

The acrylate compounds containing the perfluoroalkyl ethyl moietypreferably are members selected from the group consisting ofperfluoromethyl ethyl acrylate, perfluoroethyl ethyl acrylate,perfluoropropyl ethyl acrylate, perfluorobutyl ethyl acrylate,perfluoropentyl ethyl acrylate, perfluorohexyl ethyl acrylate,perfluoroheptyl ethyl acrylate, perfluorooctyl ethyl acrylate,perfluorononyl ethyl acrylate, perfluorodecyl ethyl acrylate,perfluoroundecyl ethyl acrylate, perfluorododecyl ethyl acrylate,perfluorotridecyl ethyl acrylate, perfluorotetradecyl ethyl acrylate,perfluoropentadecyl ethyl acrylate, perfluorohexadecyl ethyl acrylate,perfluoroheptadecyl ethyl acrylate, perfluorooctadecyl ethyl acrylate,perfluorononadecyl ethyl acrylate, and perfluoroeicosyl ethyl acrylateand mixtures thereof.

Similarly the methacrylate compounds herein preferably are membersselected from the group consisting of perfluoromethyl ethylmethacrylate, perfluoroethyl ethyl methacrylate, perfluoropropyl ethylmethacrylate, perfluorobutyl ethyl methacrylate, perfluoropentyl ethylmethacrylate, perfluorohexyl ethyl methacrylate, perfluoroheptyl ethylmethacrylate, perfluorooctyl ethyl methacrylate, perfluorononyl ethylmethacrylate, perfluorodecyl ethyl methacrylate, perfluoroundecyl ethylmethacrylate, perfluorododecyl ethyl methacrylate, perfluorotridecylethyl methacrylate, perfluorotetradecyl ethyl methacrylate,perfluoropentadecyl ethyl methacrylate, perfluorohexadecyl ethylmethacrylate, perfluoroheptadecyl ethyl methacrylate, perfluorooctadecylethyl methacrylate, perfluorononadecyl ethyl methacrylate, andperfluoroeicosyl ethyl methacrylate and mixtures thereof. It is to benoted that individual monomers or mixtures of the individual monomers ofthe perfluoroalkyl ethyl acrylates or methacrylates herein can be usedto produce the terpolymers herein. The alkyl moiety of theperfluoroalkyl ethyl acrylates or methacrylates generally contain fromabout 1 to about 20 carbon atoms, especially from about 3 to about 15carbon atoms, preferably from about 3 to about 12 carbon atoms.

The terpolymers useful in the practice of this invention can be preparedin a conventional manner by bulk, solution or dispersant polymerizationmethods using known catalysts. Thus, the terpolymers utilized by thisinvention can be prepared from the corresponding monomers with a diluentsuch as water in a heterogeneous system, usually referred to as emulsionor suspension polymerization, or with a solvent such as toluene,benzene, ethylene dichloride, methyl isobutyl ketone, 4-methyl2-pentanone or in a homogeneous system, normally referred to as solutionpolymerization. Solution polymerization for example in toluene, methylisobutyl ketone, 4-methyl 2-pentanone or a solvent having similar chaintransfer activity is the preferred method used in forming theterpolymers disclosed herein, because this method and solvent producepreferred terpolymers characterized by a molecular weight in the rangeof from about 1,000 to about 100,000. When a terpolymer is dissolved ina solvent, the solvent normally will comprise from about 40 to about 90weight percent based on the weight of the terpolymer or individualmonomers which combine to produce the terpolymer.

Polymerization of the monomers used herein readily takes place under theinfluence of heat, light and/or catalysts. Suitable catalysts includefree radical catalysts such as azo bis isobutyl nitrile and peroxidetype free radical catalysts such as benzoyl peroxide, lauryl peroxide,or t-butylhydroperoxide. The preferred free radical catalyst is azo bisisobutyl nitrile. The catalysts, when used, are employed inconcentrations ranging from a few hundreds percent to two percent byweight of the monomers. The preferred concentration is from about 0.2 toabout 1.0 percent by weight of the monomers.

Copolymerization of the monomers used herein takes place over a fairlynarrow temperature range depending upon the particular monomers andcatalyst utilized in the reaction. For example, polymerization can takeplace at temperatures from about 50° C. to about 200° C. It is to benoted that below 50° C. the terpolymer will not form in appreciableamounts and above 200° C. the terpolymer will begin to decompose. Thus,a preferred temperature range is from about 82° C. to 150° C., anespecially preferred temperature range is from about 85° C. to about120° C. The polymerization reaction is preferably carried out in aninert atmosphere, for example, nitrogen or argon to favor the formationof terpolymers that have the desired molecular weights and highviscosities. The reactions are preferably conducted at ambient pressure,however, it is to be noted that higher pressure can be used for example,pressures of from ambient pressure to about 25 psig can be employed inthe reaction.

Preferably, the polymerization reaction is carried out to substantialcompletion so that the finished product is essentially comprised of theratio of monomers introduced into the reaction vessel. Normally, areaction time of from 1 to about 72 hours, preferably from 1 to about 50hours, especially from 1 to about 10 hours, is sufficient to completethe polymerization process.

The terpolymers disclosed herein have an average molecular weight ofgreater than about 1,000, especially a molecular weight range of fromabout 1,000 to about 100,000, preferably from about 1,000 to about70,000, most preferably from about 1,000 to about 50,000.

Specific examples of terpolymers which can be used according to theinvention are the 0.01:0.001:0.009 to 1.0:1.0:0:1, especially the0.01:0.001:0.01 to 0.8:0.8:0.8, preferably the 0.01:0.001:0.01 to0.5:0.5:0.5 mole ratio terpolymer of (a) alkyl ester of unsaturatedmonocarboxylic acid, (b) olefinically unsaturated homo orheterocyclic-nitrogen compound, and (c) allyl acrylate or methacrylateor perfluoroalkyl ethyl acrylate or methacrylate.

METHOD OF PREPARATION

In a preferred method of preparation, terpolymers comprising (a) analkyl ester of carboxylic acid or a mixture of alkyl esters ofcarboxylic acid, (b) vinyl pyridine, and (c) allyl acrylate ormethacrylate or a perfluoroalkyl ethyl acrylate or methacrylate or amixture of perfluoroalkyl ethyl acrylates or methacrylates are preparedin the following manner.

Before proceeding with the reaction, the alkyl acrylate or methacrylate,vinyl pyridine, allyl acrylate or methacrylate, or perfluoroalkyl ethylacrylate or methacrylate monomers are prewashed with a 5 percent sodiumhydroxide (NaOH) solution to remove inhibitors. Alternatively, themonomers can be dried over magnesium sulfate (MgSO₄).

A 1-liter, 4-neck Pyrex glass resin kettle with detachable top and 2screw caps (manufactured by ACE Glass Inc., Vineland, N.J.) equippedwith a glass mechanical stirrer e.g., glass shaft, containing teflonblades, a heating mantle containing a thermal couple (manufactured bythe Thermal Electric Co., Saddle Brook, N.J.), a thermometer, a 250 mladdition funnel and a water cooled reflux condenser is vacuumed at 3 to5 mm of Hg to remove air and then flushed with nitrogen gas until thesystem equalized at atmospheric pressure in the resin kettle.Alternatively, a magnetic stirring bar, including apparatus can be usedto replace the glass mechanical stirrer. The top of the addition funnelwas equipped with a rubber septum and the top of the reflux condenserwith a rubber stopper containing a clear plastic vacuum tube. Theplastic tube from the rubber stopper connected to a firestone valve(manufactured by the Aldrich Co., Milwaukee, Wi.) containing a lead tovacuum and a lead to a gas source. Vacuum was supplied to the system bya Precision Vacuum Pump, Model Number DD195, manufactured by the GCACorporation, Precision Scientific Group, Chicago, Ill.

The resin kettle is charged with from about 100 ml to about 300 ml of asolvent selected, for example, from toluene, methyl isobutyl ketone,benzene or ethylene dichloride. Next, from about 0.01 to about 1.0 moleof the desired alkyl acrylate or methacrylate or mixture of alkylacrylates or methacrylates is added to the resin kettle. Examples ofsuitable alkyl acrylate or methacrylate monomers include acrylates ormethacrylates containing the methyl, ethyl, propyl, butyl, pentyl,hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl,tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl,eicosyl, heneicosyl, docosyl, tricosyl, tetracosyl, pentacosyl,hexacosyl, heptacosyl, octacosyl, nonacosyl and triacontyl moieties andmixtures thereof.

Then, from about 0.009 to about 1.0 mole of allyl acrylate ormethacrylate or 0.009 to about 1.0 mole of perfluoroalkyl ethyl acrylateor methacrylate or methacrylate (dissolved in from about 5 ml to abut100 ml of methyl isobutyl ketone) or a mixture of perfluoroalkyl ethylacrylates or methacrylates are added to the resin kettle. Examples ofperfluoroalkyl ethyl acrylates or methacrylates include the acrylates ormethacrylates containing the perfluoromethyl ethyl, perfluoroethylethyl, perfluoropropyl ethyl, perfluorobutyl ethyl, perfluoropentylethyl, perfluorohexyl ethyl, perfluoroheptyl ethyl, perfluorooctylethyl, perfluorononyl ethyl, perfluorodecyl ethyl, perfluoroundecylethyl, perfluorododecyl ethyl, perfluorotridecyl ethyl,perfluorotetradecyl ethyl, perfluoropentadecyl ethyl, perfluorohexadecylethyl, perfluoroheptadecyl ethyl, perfluorooctadecyl ethyl,perfluorononadecyl ethyl, and perfluoroeicosyl ethyl moieties andmixtures thereof.

Finally, from about 0.001 mole to about 1.0 mole of vinyl pyridine andfrom about 0.20 gram to about 1.5 grams of a free radical catalystdissolved in from about 10 ml to about 100 ml of toluene and 2 ml to 20ml of methyl isobutyl ketone are charged to the addition funnel using a50 cc glass syringe manufactured by Becton-Dickenson and Company andsold commercially by the Sargent Welch Company, Skokie, Illinois.Examples of suitable vinyl pyridines include 4-vinyl pyridine, 2-vinylpyridine and 5-ethyl-2-vinyl pyridine. Free radical catalysts whichreadily catalyze the polymerization reactions herein include azo bisisobutyl nitrile, benzoyl peroxide, lauryl peroxide and5-butylhydroperoxide.

The entire system is degassed with a vacuum pressure of from about 5 mmHg to about 25 mm Hg and flushed with nitrogen (twice). The reactionmixture in the resin kettle is heated to a temperature of from about 82°C. to about 100° C. and the mixture added to the addition funnel isslowly added to the reaction mixture in the resin kettle over a timeperiod of from about 1 hour to about 72 hours, especially 1 hour toabout 24 hours, preferably 1 hour to about 10 hours.

The foregoing method of preparation is illustrative of a preferred modefor preparing the terpolymers herein. Also in accordance with theabove-described method the 0.01:0.001:0.009 to about 1.0:1.0:1.0 moleratio terpolymers substantially as disclosed herein can be prepared byreacting the proper monomer weight ratios to produce the desiredterpolymer.

The following examples are illustrative of the invention describedherein and are not intended to limit the scope thereof.

EXAMPLE I

The method of preparation procedure was followed to prepare an alkylacrylate/vinyl pyridine/perfluoroalkyl ethyl acrylate terpolymer withthe following exceptions:

An alkyl acrylate (70 grams, 0.196 mole) designated as C₂₂ alkylacrylate was dissolved in 150 ml of toluene and added to the resinkettle. The C₂₂ alkyl acrylate was a mixture of C₁₈ to C₂₂ alkylacrylates with at least 50 percent of the acrylates having 22 carbonatoms in the alkyl group. Next, 5 grams (0.0095 mole) of aperfluoroalkyl ethyl acrylate mixture mixed with 10 ml of methylisobutyl ketone was added to the kettle. The perfluoroalkyl ethylacrylate monomer mixture had the following formula:

    CF.sub.3 CF.sub.2 (CF.sub.2).sub.K C.sub.2 H.sub.4 OC(O)CH═CH.sub.2

wherein the monomeric mixture consisted essentially of:

(1) 0-10% monomer wherein K is 4 or less;

(2) 45-75% monomer wherein K is 6;

(3) 20-40% monomer wherein K is 8;

(4) 1-20% monomer wherein K is 10; and

(5) 0.5% monomer wherein K is 12.

Then, 6 ml (0.055 mole) of 4-vinyl pyridine and 0.80 gram (0.0048 mole)of azo bis isobutyl nitrile mixed with 4 ml of methyl isobutyl ketonewere added to the addition funnel.

The mixture in the resin kettle was heated to 82° C. at atmosphericpressure and the solution of 4-vinyl pyridine and azo bis isobutylnitrile in the addition funnel was slowly added to the mixture in theresin kettle over a period of six hours.

The reaction mixture was cooled and the solvent removed by vacuum. Theproduct was a brown waxy solid (69 grams) with a yield of 86 percent.

EXAMPLE II

The method of preparation procedure was followed to prepare a C₂₂ alkylacrylate, 4-vinyl pyridine, allyl acrylate terpolymer with the followingexceptions:

The individual monomers of the terpolymer were washed with 5 percentsodium hydroxide (NaOH) and dried over magnesium sulfate (MgSO₄). To theresin kettle, was added 45 grams (0.126 mole) of C₂₂ alkyl acrylate and2 grams (0.0178 mole) of allyl acrylate) mixed with 150 ml of toluene.The C₂₂ alkyl acrylate was a mixture of C₁₈ to C₂₂ alkyl acrylates withat least 50 percent of the acrylates having 22 carbon atoms in the alkylgroup.

To the addition funnel was added 3 ml (0.027) of 4-vinyl pyridine and0.4 gram (0.0024 mole) of azo bis isobutyl nitrile dissolved in 10 ml oftoluene and 5 ml of 4-methyl 2-pentanone. Nitrogen gas was flowedthrough the system for 1/2 hour, the reaction mixture in the resinkettle was heated to 82° C. and the mixture in the addition funnel wasslowly added to the resin kettle over a period of 6 hours.

The resulting terpolymer was recovered by heating the reaction mixtureat 195° C. at 1 mm Hg for 1 hour to remove the solvent. The resultingterpolymer was a brown solid (41 grams) with a yield of 87 percent.

EXAMPLE III

The procedure of Example I is followed to produce an alkylacrylate/vinyl pyridine/perfluoroalkyl ethyl acrylate terpolymer withthe following exception:

An alkyl acrylate designated as C₁₈ alkyl acrylate is substituted forthe C₂₂ alkyl acrylate. The C₁₈ alkyl acrylate is a mixture of C₁₂ toC₂₀ alkyl acrylates with at least 50 percent of the acrylates having 18carbon atoms in the alkyl group. A terpolymer having substantiallysimilar properties to the terpolymer of Example I is produced.

EXAMPLE IV

The procedure of Example II was followed to produce a terpolymer withthe following exceptions:

An alkyl acrylate designated as C₁₈ alkyl acrylate (33 grams) wassubstituted for the C₂₂ alkyl acrylate. In addition, 11.2 grams of allylacrylate and 10 ml of 4-vinyl pyridine were used in the reaction. Theterpolymer produced had substantially similar properties to theterpolymer of Example II.

EXAMPLES V to VIII

The pour point enhancing properties of the terpolymers produced inExamples I and II were tested in accordance with the procedure set forthin ASTM-D97. The pour point properties of the terpolymers of Examples Iand II were compared with a blank and with Shellswim 5X® and ShellswimIIT®, two well known pour point depressants marketed commercially by theShell Oil Company, Houston, Tex. All of the additives were added to theoil composition at concentrations of 1,000 ppm active and 46.11° C.preheat.

                                      TABLE 1                                     __________________________________________________________________________              Pour Point (°C.)                                                Crude      Terpolymer                                                                           Terpolymer                                                                           Shellswim                                                                           Shellswim                                   Ex.                                                                              Oils   Blank                                                                             of Ex. I.sup.(1)                                                                     of Ex. II.sup.(2)                                                                    5X.sup.(3)  ®                                                                   11T.sup.(4)  ®                          __________________________________________________________________________    V  Bombay 29.44                                                                             7.22   -3.89  10.00 12.78                                       VI Kotter 26.67                                                                             10.00  10.00  10.00 7.22                                        VII                                                                              Delhi 87                                                                             26.67                                                                             18.33  21.11  21.11 21.11                                       VIII                                                                             New Zealand                                                                          32.22                                                                             21.11  --     21.11 21.11                                       __________________________________________________________________________     .sup.(1) Terpolymer of Ex. I  C.sub.18 -C.sub.22 alkyl acrylate/4vinyl        pyridine/C.sub.3 -C.sub.15 fluoroalkyl ethyl acrylate                         .sup.(2) Terpolymer of Ex. II  C.sub.18 -C.sub.22 alkyl acrylate/4vinyl       pyridine/allyl acrylate                                                       .sup.(3) Shellswim 5X ® A C.sub.18 -C.sub.22 alkylacrylate ester          homopolymer. Sold commercially by the Shell Oil Co., Houston, Texas           .sup.(4) Shellswim 11T ® A C.sub.18 -C.sub.22 alkylacrylate and 4viny     pyridine copolymer sold commercially by the Shell Oil Company, Houston        Texas                                                                    

As can readily be determined from the above test results, theterpolymers produced according to the procedure set forth herein gavesuperior or comparable pour point results when compared to commercialpour point additives for crude oils.

It should be noted that the methacrylate analogue of the acrylatemonomers used to formulate the terpolymers herein may be substituted forthe acrylate analogues herein with similar results and pour pointproperties.

Obviously, many modifications and variations of the invention, as hereinabove set forth, can be made without departing from the spirit and scopethereof, and therefore only such limitations should be imposed as areindicated in the appended claims.

I claim:
 1. An alkyl ester of unsaturated monocarboxylic acid anolefinically unsaturated homo or heterocryclic-nitrogen compound andallyl acrylate or methacrylate terpolymer having pour point depressantproperties, said terpolymer comprising the reaction product of (a) amonomeric alkyl ester of carboxylic acid or a mixture of alkyl esters ofcarboxylic acid having the formula: ##STR4## wherein R is H or CH₃ andR₁ is alkyl having from about 1 to about 30 carbon atoms; (b) vinylpyridine; and (c) an allyl acrylate or methacrylate.
 2. The terpolymerof claim 1 wherein components (a), (b), and (c) are reacted in a moleratio of from about 0.01:0.001:0.009 to about 1.0:1.0:1.0, saidterpolymer having a molecular weight of at least about 1,000.
 3. Theterpolymer of claim 1 has a molecular weight of from about 1,000 toabout 100,000.
 4. The terpolymer of claim 1 wherein R₁ of component (a)is alkyl having from about 4 to about 28 carbon atoms.
 5. The terpolymerof claim 1 wherein the monomeric alkyl ester of carboxylic acid ofcomponent (a) is a member selected from the group consisting of methylacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentylacrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonylacrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate, tridecylacrylate, tetradecyl acrylate, pentadecyl acrylate, hexadecyl acrylate,heptadecyl acrylate, octadecyl acrylate, nonadecyl acrylate, eicosylacrylate, heneicosyl acrylate, docosyl acrylate, tricosyl acrylate,tetracosyl acrylate, pentacosyl acrylate, hexacosyl acrylate, heptacosylacrylate, octascosyl acrylate, nonacosyl acrylate and triacontylacrylate and mixtures thereof.
 6. The terpolymer of claim 1 wherein thevinyl pyridine of component (b) is a member selected from the groupconsisting of 2-vinyl pyridine, 4-vinyl pyridine and 5-ethyl-2-vinylpyridine and mixtures thereof.
 7. The terpolymer of claim 1 wherein thevinyl pyridine of component (b) is 4-vinyl pyridine.
 8. A terpolymerhaving pour point depressant properties which is obtained by freeradical polymerization of a monomeric mixture comprising from about 0.01to about 1.0 mole percent of (a) an alkyl ester of carboxylic acid or amixture of alkyl esters of carboxylic acid having the formula: ##STR5##wherein R is H or CH₃ and R₁ is alkyl having from about 1 to about 30carbon atoms; (b) from about 0.01 to about 0.1 mole percent of vinylpyridine; and (c) from about 0.01 to about 1.0 mole percent of an allylacrylate or methacrylate, said terpolymer having a molecular weight ofat least about 1,000.
 9. The terpolymer of claim 8 having a molecularweight of from about 2,000 to about 50,000.
 10. The terpolymer of claim8 wherein R₁ of component (a) is alkyl having from about 4 to about 28carbon atoms.
 11. The terpolymer of claim 8 wherein the monomeric alkylester of carboxylic acid of component (a) is a member selected from thegroup consisting of butyl methacrylate, pentyl methacrylate, hexylmethacrylate, heptyl methacrylate, octal methacrylate, nonylmethacrylate, decyl methacrylate, undecyl methacrylate, dodecylmethacrylate tridecyl methacrylate, tetradecyl methacrylate, pentadecylmethacrylate, hexadecyl methacrylate, heptadecyl methacrylate, octadecylmethacrylate, nonadecyl methacrylate, eicosyl methacrylate, heneicosylmethacrylate, docosyl methacrylate, tricosyl methacrylate, tetracosylmethacrylate, pentacosyl methacrylate, hexacosyl methacrylate,heptacosyl methacrylate, and octacosyl methacrylate and mixturesthereof.
 12. The terpolymer of claim 8 wherein the vinyl pyridine ofcomponent (b) is a member selected from the group consisting of 2-vinylpyridine and 4-vinyl pyridine and mixtures thereof.
 13. The terpolymerof claim 8 wherein the vinyl pyridine of component (b) is 4-vinylpyridine.